The website from which you got to this page is protected by Cloudflare. Email addresses on that page have been hidden in order to keep them from being accessed by malicious bots. You must enable Javascript in your browser in order to decode the e-mail address.| www.validity.com
SMTP Error Codes| senders.yahooinc.com
This resource is for qualified high-volume senders. If you’re an everyday Gmail user| www.gmail.com
This document describes a method for signaling a one-click function for the List-Unsubscribe email header field. The need for this arises out of the actuality that mail software sometimes fetches URLs in mail header fields, and thereby accidentally triggers unsubscriptions in the case of the List-Unsubscribe header field.| IETF Datatracker